THE GENUS ACRONYCTA AND ITS ALLIES. 75 



trapezoidals being very long, those on ii very short, on 5-10 

 nearly twice the diameter of the larva in length, the others 

 longer ; the posterior trapezoidal hairs on 12 have the appear- 

 ance of belonging to the anterior trapezoidal set, being equally 

 long and merging with them. 



In the 2nd skin the larva is blacker, hairs longer, tubercles 

 so large on 2nd, 5th, and especially on 12th, as to look like 

 humps, the dorsal hairs are black, the lateral white ; the dorsal 

 band is pale lemon yellow (almost white) visible only on the 

 pale segments, till the larva is well grown, when this area on the 

 dark segments is paler than the rest of the segment, and there 

 is then on 6 and 7 a trace of a vertical white mark in front and 

 behind the spiracular tubercles. The post-spiracular tubercle 

 is still of good size, the area below it is paler, and the effect of 

 the longitudinal form of the sub-spiracular tubercle is to show 

 a paler line above the darker tubercles, the tubercles (anterior 

 trapezoidal) of 5 already approach one another. Those of 12 

 are large, but the area between them is but slightly paler than 

 the rest of the larva, 13 is pale rufous, slightly paler than 12, but 

 there is no white cross on 12, no white diamonds between 

 trapezoidals, no rich colour of 13, and the hump on 5 is not so 

 distinct as in tridens. 



In the 3rd skin it has the psi appearance of the full-grown 

 larva, the yellow dorsal band is continuous on 3-4,6-11, and on 

 13, but the yellow is of a brownish tint on 8 and g ; the anterior 

 trapezoidals on these segments are now very small. , There is 

 now a distinct hump on 5th segment, but still recognisable as 

 consisting of anterior trapezoidals ; most of the tubercles 

 carry 5-8 hairs, those of dark segments rather the longest and 

 generally black. The sides are rufo-fuscous, marbled with 

 yellowish fuscous, with black tubercles and two pale vertical 

 lines in front and behind the spiracular tubercles. The sub- 

 spiracular tubercles of 11 and 12 are yellow, others black. 



In the 4th and following skins it gradually assumes the well- 

 known appearance of the full-grown larva. 



Its habits of pupating seem to be identical with those of 

 tridens already noticed. The pupa (PI. III., figs, i, \a, ib) is 

 not to be distinguished with certainty from that of tridens. 

 Psi usually has four spines on each side forming the ventral 

 portion of the anal armature, whilst tridens usually has but 

 three, but just as tridens has not unfrequently four, so psi has 

 at times only three. Tridens is also usually smaller and more 

 delicate and transparent in appearance, and I cannot with cer- 



